Modular building unit for a protective shelter

ABSTRACT

A composite panel assembly comprising at least one modular building unit. The modular building unit of the present invention may comprise two tubes aligned immediately adjacent, oriented parallel to each other, and having an integral connection over at least one portion of their outer circumferences. The volume surrounding the integrated tubes may be coated with a wide variety of function specific structural materials, and yet further, the inner diameter of the tubes may be filled with a wide variety of function specific filler materials. The composite panel assembly may be used in a wide variety of construction applications including, but not limited to, load bearing and impact resistant structures. One such application is a protective shelter that can be assembled in a pre-existing structure using common hand tools. The shelter may be assembled from the inside, and is resistant to both high winds and airborne missiles.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of provisional patent application Ser. No. 60/785,113, filed with the USPTO on Mar. 23, 2006, which is incorporated by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISK

Not applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to the field of construction, and more particularly to a modular building unit that may be utilized to construct a protective shelter for enclosing the interior of a pre-existing room during a high-wind incident.

2. Background Art

High wind storms can cause significant structural damage resulting in substantial economic loss, significant injuries, and loss of life as was evident from hurricanes striking the coastal regions of Louisiana, Texas and Florida in recent years. Structural failure in high wind conditions is a significant factor contributing to economic loss, injuries and fatalities sustained by affected home and business owners.

The Federal Emergency Management Agency (FEMA) has established criteria for in-residence shelters to protect the inhabitants of buildings from natural disasters. These shelters are “to provide a high degree of occupant protection during severe windstorms (hurricanes and tornadoes).” In-Residence Shelter, October, 1998. This FEMA publication provides construction plans and drawings for several different types of shelters including an in-ground shelter, a basement lean-to, a corner location basement shelter, a Concrete Masonry Unit (CMU), a CMU/concrete shelter, and a wood-frame shelter with plywood sheathing or steel wall sheathing.

There is also a published pamphlet sponsored by FEMA and written by the Wind Engineering Research Center of Texas Tech University entitled, “Taking Shelter from the Storm: Building a Safe Room Inside Your House” (Second Ed., March 2004), listed as publication FEMA 320. The publication states that the basis of the design of a shelter “is to provide a space where you and your family can survive a tornado or hurricane with little or no injury . . . To protect the occupants during extreme windstorms, the shelter must be adequately anchored to the house foundation to resist overturning and uplift. The connections between all parts of the shelter must be strong enough to resist failure, and the walls, roof, and door must resist penetration by windborne missiles.” However, the pamphlet further states that extensive testing has shown that “walls, ceilings, and doors commonly used in house construction cannot withstand the impact of missiles carried by extreme winds.” The publication then describes shelter designs that meet the design criteria.

All of the shelters in the FEMA publication involve permanent construction using concrete as the primary material or as the foundation material. The installation of these shelters thus cannot be performed by the average homeowner and requires the use of a professional builder. For example, the wall construction recommended for a typical frame shelter plan with plywood and steel wall sheathing includes two layers of three-quarter inch plywood panels on the outside, a 14 gauge steel sheathing on the inside and double 2×4 studs at 16 inches on center.

FEMA shelters have the following design criteria: they will withstand wind pressures developed from 250-MPH, 3-second gusts in accordance with ASCE 7-95; they will withstand windborne debris (missile) impact loads created by a 15 pound 2×4 traveling horizontally along the board's longitudinal axis at 100 mph, traveling vertically at 67 mph, and impacting perpendicular to the wall surface. This missile speed corresponds to a 250 mph wind. The tornado missile test criteria were established by the Wind Engineering Research Center (WERC) at the Texas Tech University. FEMA set another criterion for in-ground shelters wherein there must be a minimum of five square feet per person.

The shelter design criteria have contradictory requirements: on the one hand the shelters must be physically strong so they can withstand high wind and earthquake forces; and the shelters must also be able to withstand the penetration of windborne articles. If the shelter is constructed pursuant to the plans in the aforementioned FEMA publication, it can easily meet both of these contradictory criteria. However, such a shelter must be constructed by a professional building contractor having a number of different professional workers, each with one of the requisite construction skills such as masonry, carpentry, and iron work.

There are many U.S. patents that disclose a multitude of shelters. Invariably, all of these shelters have the primary goal of providing structural integrity and protecting against collapse, ignoring the protection against the penetration of windborne articles. One issued patent, U.S. Pat. No. 5,813,174 to Waller, discloses a light-weight steel structure that can be packaged and shipped as loose tubular and bent-plate channel modules and can be assembled by the user. Its disclosure states that the structure can be assembled entirely from within the structure as it is being built, and thus it can be installed in a pre-existing enclosure. It appears that an embodiment of this patent is presently being marketed by the Remagen Corporation of Monteagle, Tenn. However, the intent of this patent is to produce a structure comprised of a plurality of metal panels bolted together to produce extremely rigid walls that provide a solid enclosure. The construction features set forth in the patent clearly describe an I-beam configuration between adjacent panels that are connected to a rigid frame. For example, FIG. 5 of the patent discloses a rigid frame that is comprised of square, hollow steel tubes that defines the parallelepiped shape of the structure. Each end of each wall panel has a rigid metal cap that is fixedly connected to the frame to provide increased rigidity.

The difficulty with very rigid and solid structures is that they will not pass the FEMA penetration test due to their high rigidity. Such structures are designed to protect against building collapse. The walls have virtually no “give” or “play”, and thus no means for absorbing and distributing the striking force of a propelled object (e.g. a 2×4 beam traveling at over 100 miles per hour). Page 12 of the publication FEMA 320 states, “[d]amage can also be caused by flying debris (referred to as windborne missiles). If wind speeds are high enough, missiles can be thrown at a building with enough force to penetrate windows, walls, or the roof . . . Even a reinforced masonry wall will be penetrated unless it has been designed and constructed to resist debris impact during extreme winds. Because missiles can severely damage and even penetrate walls and roofs, they threaten not only buildings but the occupants as well.”

Thus, there is a need for a protective shelter that will not only meet the aforementioned FEMA criteria, but can also be assembled by the consumer without the need for professional builders. Further, there is also a need for a shelter that can be installed within a pre-existing structure and does not require installation prior to construction of the structure. Still further, there is a need for a shelter that can be economically purchased and easily assembled with common hand tools. It is thus clear that well recognized need exists for an economical protective shelter that can be assembled by everyday consumers, from prefabricated components with readily available hand tools in a short period of time, and when assembled can pass both FEMA's structural integrity test and missile penetration test.

Thus, it would be useful to provide a protective shelter capable of installation within a pre-existing structure, using common hand tools, and not requiring an extensive structural foundation.

BRIEF SUMMARY OF THE INVENTION

In accordance with one embodiment, a composite panel assembly is disclosed comprising at least one modular building unit that comprises: a first tube; a second tube aligned immediately adjacent and parallel to the first tube; and at least one integral connection between the outer circumference of the first tube and the outer circumference of the second tube.

Such composite panel assemblies may be further utilized in the construction of a protective shelter that protects an inner space. The protective shelter comprises: a front wall, the front wall having a door frame assembly therein and a door attached to the door frame assembly; a rear wall; two side walls; and a ceiling panel; wherein the walls and the ceiling panel each comprise a composite panel assembly, the composite panel assembly comprises a plurality of modular building units, each of the modular building units comprises a first tube, a second tube aligned immediately adjacent and parallel to the first tube, and at least one integral connection between the outer circumference of the first tube and the outer circumference of the second tube.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 is a top view of an embodiment of a modular building unit in accordance with the present invention.

FIG. 2 is a top view of an embodiment of a modular building unit coated with structural material in accordance with the present invention.

FIG. 3 is a side view of an embodiment of a modular building unit in accordance with the present invention.

FIG. 4 is a top view of one embodiment of a composite panel assembly in accordance with the present invention.

FIG. 5 is a top view of one embodiment of a modular building corner unit in accordance with the present invention.

FIG. 6 is a top view of one embodiment of a modular building corner unit coated with structural material in accordance with the present invention.

FIG. 7 is an elevated perspective view of one embodiment of a protective shelter in accordance with the present invention.

FIG. 8 is an elevated perspective view of one embodiment of a front wall composite panel assembly further comprising a door frame assembly and a door in accordance with the present invention.

FIG. 9 is a top view of one embodiment of a composite panel assembly in accordance with the present invention depicting a connecting means secured to the modular building units by typical bolts and receiving nuts.

FIG. 10 is a top view and side view of one embodiment of a receiving nut disposed within the lower portion of the modular building unit in accordance with the present invention.

FIG. 11 is a top view and side view of one embodiment of a receiving nut disposed within the upper portion of the modular building unit in accordance with the present invention.

FIG. 12 is a cut away side view of one embodiment of a connecting means securing modular building units to both the base and ceiling panel in accordance with the present invention.

FIG. 13 is a top view of one embodiment of a protective shelter in accordance with the present invention, having the ceiling panel removed for clarification purposes.

FIG. 14 is an elevated perspective view of one embodiment of a door frame assembly in accordance with the present invention.

FIG. 15 is an elevated perspective view of one embodiment of a door in accordance with the present invention.

FIG. 16 is a top view of one embodiment of a modular building unit in accordance with the present invention.

FIG. 17 is an elevated perspective view of one embodiment of a composite panel assembly in accordance with the present invention.

FIG. 18 is a top view of one embodiment of a modular building corner unit in accordance with the present invention.

FIG. 19 is an elevated perspective view of one embodiment of a modular building corner unit and adjacent modular building unit in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. Unless otherwise defined, technical and scientific terms herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Suitable methods and materials are described below; additionally however, methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. In addition, the materials, methods and examples given are illustrative in nature only and not intended to be limiting. Accordingly, this invention may be embodied in many different forms and should not be construed as limited to the illustrated embodiments set forth herein. Rather, these illustrated embodiments are provided solely for exemplary purposes so that this disclosure will be thorough and complete, and will convey the scope of the invention to those skilled in the art. Other features and advantages of the invention will be apparent from the following detailed description.

Referring now to FIGS. 1-6, a composite panel assembly 10 in accordance with the present invention will be described. The composite panel assembly 10 comprises at least one modular building unit 20, preferably a composite panel assembly 10 comprises a plurality of modular building units 20 attached to each other.

As depicted in FIG. 1, the modular building unit 20 is formed from a first tube 22 and a second tube 24 having at least one integral connection 26 between the outer circumference of the first tube 22 and the outer circumference of the second tube 24. Tubes 22, 24 are preferably composed of readily available steel, however, tube 22, 24 composition material may include, but is not limited to, other metals, composite materials, polymeric materials, any combination thereof, and any other structural materials known within the art.

The integral connection 26 may be provided for in a wide variety of configurations including, but not limited to, a single connection point, one continuous connection along the majority of the lengths of tubes 22, 24, connections at approximately the midpoint and both ends of the tubes 22, 24, uniformly spaced connections along the length of the tubes 22, 24 (depicted in FIG. 3), and any other connection configurations known within the art. Further, integral connection 26 may be provided for via a variety of methods including, but not limited to, a welded connection, a laminate bond, an epoxy bond, a polyurethane bond, an acrylic bond, a cyanoacrylate bond, a silicone bond, and any other connection methods known within the art for each particular tube 22, 24 material.

As depicted in FIG. 2, a structural material 28 may be deposited onto the exterior surface of the modular building unit 20. Structural material 28 may serve to enhance the function and/or characteristics of the underlying tube 22, 24 materials. Beneficial attributes of the structural material may include, but are not limited to, protecting modular building unit 20, strengthening modular building unit 20, improving the durability of modular building unit 20, improving impact resistance of modular building unit 20, improving the connection strength between at least two modular building units 20, and any other beneficial coating attributes known within the art. Suitable structural materials 28 that may impart such characteristics include, but are not limited to, polymeric materials (e.g., polyvinyl chloride, polyurethane, etc.), rubberized materials, composite materials (e.g. KEVLAR®, which comprises fibers formed from long molecular chains produced from poly-paraphenylene terephthalamide), cement materials, and any other materials known within the art.

As depicted in FIG. 4, a composite panel assembly 10 may be formed from a plurality of attached modular building units 20 disposed within the same plane. The attachments 29 between adjacent modular building units 20 may be similar to the integral connections 26 between tubes 22, 24. Such attachments 29 between the abutting tubes of immediately adjacent modular building units 20 may include, but are not limited to, a welded connection, a laminate bond, an epoxy bond, a polyurethane bond, an acrylic bond, a cyanoacrylate bond, a silicone bond, and any other connection methods known within the art for the selected tubular material. The configuration for attachment 29 may be selected from the same wide variety as described for the integral connection 26. In a preferred embodiment, integral connection 26 is a welded connection and attachment 29 is an epoxy bond.

The modular building units 20 of composite panel assembly 10 may have an optional coating of structural material 28, as described above, disposed about the outer circumference of tubes 22, 24. In a preferred embodiment depicted in FIG. 2, the structural material 28 is disposed about the modular building unit 20 such that the external surface of the coated modular building unit 20 has a rectangular cross section. In one configuration, a portion of said outer circumference of tubes 22, 24 that is diametric to the integral connection 26 remains uncovered by the structural material 28. Such a configuration, as shown in FIG. 2 and FIG. 4, allows for the direct attachment 29 of abutting tubes 22, 24 in immediately adjacent modular building units 20. Additionally, abutting structural material 28 portions of immediately adjacent modular building units 20 may be bonded together to provide a contiguous outer surface to the composite panel assembly 10. Such structural material 28 to structural material 28 bonding may also serve to further strengthen and reinforce the attachment 29 junctions between adjacent modular building units 20.

A modular building corner unit 30 may be used in connecting two composite panel assemblies 10. FIG. 5 depicts a modular building corner unit 30 comprising a corner tube 32, a first side tube 34 and a second side tube 36, wherein said side tubes 34, 36 are attached to corner tube 32 by respective integral connections 26. FIG. 5 depicts side tubes 34, 36 connected to corner tube 32 forming an orthogonal modular building corner unit 30. Such an orthogonal configuration is a preferred embodiment, however, the scope of the present invention includes all possible corner angles desired by a user, subject only to the abutment of constituent side tube 34, 36 material. Structural material 28, as described above and depicted in FIG. 6, may be deposited onto the exterior surface of the modular building corner unit 30.

Filler material may optionally be disposed within the tubes 22, 24 of each modular building unit 20 and modular building corner unit 30. Filler materials enable a dramatic increase in the strength and impact resistance of the modular building units 20. Appropriate filler material may include, but is not limited to, cement, steel (e.g. steel rods disposed within tubes 22, 24), foam (e.g. high density foam), polymers (e.g. polyurethane), any combinations thereof, and any other filler materials known within the art. Use of such strengthening filler material allows the possibility of using a more economical material for tubes 22, 24 of the modular building units 20. As an example, with use of an appropriate filler material a user may opt for a lower grade standard metal fence post instead of ¼ inch steel pipe as the chosen material for pipes 22, 24.

Composite panel assemblies 10, as described above, are capable of use in a wide variety of construction functions. Such utility includes, but is not limited to, vertical structures such as walls and barriers, and horizontal structures such as decks, floors, roofs, and the like. Use of a plurality of strong and impact resistant composite panel assemblies together allows a user to construct a very safe definable space. Examples include safe rooms or storm rooms to protect people from harmful outside actions and forces. As an example, such a protective shelter would be highly advantageous in providing protection from tornadoes in the Midwest and hurricanes in the Southeast.

FIGS. 7-15 depicts a protective shelter 100 and its constituent elements. As viewed in FIG. 7, shelter 100 comprises a front wall 40, a rear wall 42, a left side wall 44, a right side wall 46, and a roof panel 48. A door frame assembly 50 may be disposed within the front wall 40. A movable door 52 may be attached to door frame assembly 50 through which access to shelter 100 can be gained. Movable door 52 may swing into shelter 100, swing out of shelter 100, slide parallel to front wall 40, or perform any other movable door function known in the art to allow access to the protective shelter 100. Shelter 100 rests on a base, wherein the base may be a floor constructed of any conventional building material, preferably being a concrete slab or cement floor.

A preferred embodiment of the protective shelter 100 of the present invention is depicted in FIG. 7. The walls 40, 42, 44, 46 and roof panel 48 may comprise a plurality of modular building units 20, each wall 40, 42, 44, 46 extending the height of the room walls and attached to adjacent modular building units 20 down the length of each room wall or to a modular building corner unit 30 at a room corner.

After determining the dimensions of the room to be retrofitted, an appropriate number of modular building units 20 are joined along the length of each interior wall of the pre-existing structure via an attachment 29. Similarly each modular building corner unit 30 is joined to adjacent tubes 22, 24 of modular building units 20 via attachment 29. The combined length of adjacent modular building units 20 and joined modular building corner units 30 at each corner along a wall may equal the length of each room wall. The length of a modular building corner unit 30 may approximately equal that of a modular building unit 20. Walls 40, 42, 44, 46 incident to a corner without a modular building corner unit 30 from the orthogonal adjacent wall 40, 42, 44, 46 will include an attached modular building corner unit 30. Alternatively, the modular building units 20 and modular building corner units 30 may be sized during the manufacturing process so that the appropriate number of modular building units 20 extends the length of the inner surface of each room wall.

After room wall interior surfaces are fitted with adjacent modular building units 20 and room corners include modular building corner units 30, connecting means 54 may be used to further secure each modular building unit 20 to adjacent unit(s) 20 or corner unit(s) 30 along a wall 40, 42, 44, 46 or roof panel 48 (see FIG. 9). The connecting means 54 for further securing modular building units 20 of a wall 40, 42, 44, 46 or ceiling panel 48 to each other may comprise a flat bracket or any other connecting means known within the art. The function of connecting means 54 may further include securing the walls 40, 42, 44, 46 to both the ceiling panel 48 and the base (e.g. floor or slab), as shown in FIG. 12. In a preferred embodiment depicted in FIGS. 8, 9, 12 and 13, connecting means 54 may comprise an L-bracket as is commonly used in the art. Connecting means 54 may also comprise any other connectors known to one of ordinary skill in the art.

Connecting means 54 may be attached to walls 40, 42, 44, 46 in any manner known within the arts including, but not limited to, welding, conventional bonding, and the use of typical nuts, bolts and/or screws. A preferred embodiment comprises typical bolt(s) 56 and complementary receiving nut(s) 58, as shown in FIGS. 9-12. Receiving nuts 58 may comprise individual components or may be provided in the form of a nut plate if more than one bolt 56 is to be used per tube 22, 24. As depicted in the preferred embodiment, at least one hole in connecting means 54 is aligned with at least one fastening hole 60 formed within the upper and lower ends of tubes 22, 24 of the modular building unit(s) 20. The fastening hole(s) 60 may be centered on the exposed circumference of the respective tubes 22, 24 of the modular building units 50 (see FIGS. 9 and 10). In such an embodiment, the bolts 56 and nuts 58 secure connecting means 54 to the modular building units 20 further securing the modular building units 20 of a composite panel assembly 10 to each other. Although this embodiment depicts the use of L-brackets as the connecting means 54 positioned at the top and bottom of adjacent modular building units 20, any number of clamps or other connecting means 54 may be used at any respective position. In addition, any method appreciated by one of skill in the art may be used to effectively secure the adjacent modular building units 20 of the room walls 40, 42, 44, 46 to each other, and to the roof panel 48 and base, respectively.

A roof panel 48 is composed of adjacent modular building units 20 similar to the units 20 used in composing the room walls 40, 42, 44, 46, as discussed above. As shown in FIG. 7, the tubes 22, 24 of the roof panel 48 may extend the width or length of the room as opposed to the height of the room in any pre-existing structure. A plurality of modular building units 20 are attached to one another, as described above, to form the roof panel 48 that is set atop the walls 40, 42, 44, 46 of the protective shelter 100. Similar to the wall 40, 42, 44, 46 constructions, a connecting means 54 may be used to further attach the modular building units 20 of the roof panel 48 to each other, and may further serve to secure the roof panel 48 to the upper portion of the walls 40, 42, 44, 46. Tubes 22, 24 comprising the modular building units 20 of the roof panel 48 may have at least one fastening hole 60 at each end of the respective tubes 22, 24. Such at least one fastening holes 60 may align with holes within a connecting means 54 attached to the upper portion of each wall 40, 42, 44, 46. The connecting means 54 may then be secured to the roof panel 48 by any means known within the art, with a preferred embodiment comprising typical bolts 56 and receiving nuts 58 depicted in FIG. 12. Additionally, a tube 22, 24 of the last modular building unit 20 on both ends of roof panel 48 may have fastening holes 60 along the length of the tube 22, 24 for attachment of connecting means 54 capable of securing roof panel 48 to the upper tube 22, 24 ends of the respective walls 40, 42, 44, 46 (e.g. see specifically front wall 40, back wall 42, and roof panel 48 of FIG. 7). In a preferred embodiment, the connecting means 54 is an L-bracket abutted into the intersection corner between the roof panel 48 and a wall 40, 42, 44, 46.

The modular building units 20 of the walls 40, 42, 44, 46 can be secured to the base or floor via connecting means 54 in the same method in which they were secured to the roof panel 58 above. Connecting means 54 may include a portion for securing to the lower end of tubes 22, 24 of walls 40, 42, 44, 46 and another portion for securing to the base. As with the roof panel 48 above, any other method known to one of skill in the art may be used in securing the walls 40, 42, 44, 46 of the protective shelter 100 to the base. The base or flooring may include pre-drilled holed coinciding with holes within connecting means 54, into which screws are passed thereby securing the shelter 100 to the floor. All means of securing the connecting means 54 to the roof panel 48, walls 40, 42, 44, 46, and base may be accessible from the inside of the shelter to permit its construction from within the protected space.

As depicted in FIG. 8, any room door may be retrofitted or replaced with a door 50 formed of adjacent modular building units 20, as disclosed above. An appropriate door hinge or door slide is preferably capable of withstanding the torque and forces for storm room requirements disclosed by FEMA. FIG. 14 shows one embodiment of a door frame assembly 52 to which an appropriate door hinge or slide may be attached. Similar to the wall 40, 42, 44, 46 and roof panel 48 constructions, the door 50 (see FIG. 15) may comprise adjacently attached modular building units 20 that may be further secured to one another using a connecting means 54, as discussed above. The movable door 50 may be utilized in place of or retrofitted over the door of the pre-existing structure.

Another embodiment of a modular building unit 20 and protective shelter 100 in accordance with the present invention will now be described in reference to FIGS. 16-19. Means of construction are similar to those disclosed above, with some minor differences discussed herein.

FIG. 16 depicts another embodiment of a modular building unit 70. The modular building unit 70 comprises an I-beam 72 and a tubular member 74. I-beam 72 may comprise a first flange 76 disposed parallel to a second flange 78, wherein the first flange 76 and the second flange 78 are connected by a web 80. The web 80 is disposed perpendicular to both the first flange 76 and the second flange 78. Tubular member 74 may be disposed parallel to the longitudinal axis of the I-beam 72, wherein half of the outer circumference of the tubular member 74 is positioned within the I-beam 72 between the first flange 76 and the second flange 78, as depicted in FIG. 16. Modular building unit 70 may further comprise positioning material 82 disposed within the I-beam 72 between the first flange 76 and the second flange 78 for maintaining approximately half of the outer circumference of the tubular member 74 within the I-beam 72 between its first flange 76 and its second flange 78.

The positioning material 82 serves to hold the tubular member 74 at the weakest part of the I-beam 72. Positioning material 82 may include, but is not limited to, polyurethane, other polymers, cement, foams, composite materials, and any other materials known within the art. The exposed surface of positioning material 82 may be formed in a concave shape that is complimentary to the external circumference of the tubular member 74, as shown in FIG. 16. The concave shape may be obtained during the manufacture of the I-beam 72 or during the retrofit procedure. Further, the exposed surface of positioning material 82 may have an adhesive disposed thereon to assist in maintaining the position of tubular member 74.

FIG. 17 depicts a plurality of modular building units 70 disposed within the same plane and in an alternating arrangement of I-beams 72 and tubular members 74. In such a configuration, the tubular members 74 serve to reinforce and support the weakest portion of the I-beams 72. With each modular building unit 70 comprising an I-beam 72 and a tubular member 74, a tubular member 74 of a first modular building unit 70 may be disposed within the open side of an I-beam 72 of a second modular building unit 70 in a repeating manner, as seen in FIG. 17. Similar to the disclosure above, to further secure the modular building units 70 to each other, a connecting means 54 may be disposed across the junctions of the modular building units 70. FIG. 17 depicts at least one fastening hole 84 on each modular building unit by which a connecting means 54 may be secured. Such a connecting means 54 may be attach to the modular building units 70 at any position and in any number desired across the secured panel. The method for securing the connecting means 54 to the panel of modular building units 70 may be any means known within the art, with a preferred embodiment being a typical bolt and receiving nut.

Another embodiment of a protective shelter 100 may comprise a plurality of modular building units 70 combined in a manner similar to the above disclosed shelter 100 constructions using modular building units 20. Walls, a roof panel and a door may be constructed from a panelized plurality of modular building units 70, as depicted in FIG. 17. FIGS. 18 and 19 depict an embodiment of a modular building corner unit 90. As shown in FIG. 18, two I-beams may be combined into a modular building corner unit 90. By cutting away one leg of a flange on both I-beams, the cut legs and normal legs may, respectively, abut and may be fixedly attached to each other by any means known within the art. In a preferred embodiment, the two I-beams may be welded together to form the modular building corner unit 90 in FIG. 18. The I-beams 72 and tubular members 74 of the modular building units 70 are cut to lengths equal to the height of the room to be retrofitted. Similarly, an appropriate number of modular building units 70 may be incorporated in forming walls that match the dimensions of the room within the pre-existing structure. Modular building corner units 90 may be utilized to connect panelized wall portions at the corners of the pre-existing room. Adjacent modular building units 70 may be secured together via connecting means 54, as done with modular building units 20, fastening holes 60, with the preferred method using nuts and bolts, as described above.

The I-beams 72 and tubular members 74 of each modular building panel 70 of the roof panel extends the length or width of the room to be retrofitted, as discussed above with the modular building units 20. Similarly, the walls of the shelter 100 may be fixedly connected to both the base and the roof panel via connecting means 54, which may be secured at both the upper and lower portion of each adjacent I-beam 72 constituent of the shelter 100 walls. Attachment of connecting means 54 to the roofs, walls, and base can be in any manner known in the art. A preferred means of attaching the connecting means is via typical nuts and bolts, as discussed above for the first embodiment of the protective shelter 100.

In the drawings and specification, there have been disclosed typical preferred embodiments of the invention, and all though specific terms are employed, the terms are used in a descriptive sense only and not for purposes of limitation. The invention has been described in considerable detail with specific references to these illustrated embodiments. It will be apparent, however, that various modifications and changes can be made within the spirit and scope of the invention as described in the forgoing specification.

While the above description contains many specificities, these should not be construed as limitations on the scope of any embodiment, but as exemplifications of the presently preferred embodiments thereof. Many other ramifications and variations are possible within the teachings of the various embodiments.

Thus the scope of the invention should be determined by the appended claims and their legal equivalents, and not by the examples given. 

1. A composite panel assembly, comprising: at least one modular building unit, comprising, a first tube; a second tube aligned immediately adjacent and parallel to said first tube; and at least one integral connection between the outer circumference of said first tube and the outer circumference of said second tube.
 2. The composite panel assembly of claim 1, wherein a first modular building unit is attached to a second modular building unit, said modular building units being disposed parallel, within the same plane, and having an attachment between said outer circumference of one of said tubes of said first modular building unit and said outer circumference of one of said tubes of said second modular building unit.
 3. The composite panel assembly of claim 2, wherein a filler material is disposed within said tubes.
 4. The composite panel assembly of claim 1, further comprising a structural material disposed about the outer surface of said modular building units.
 5. The composite panel assembly of claim 4, wherein said structural material is disposed in a manner providing the outer surface of said structural material a rectangular cross section, a portion of said outer circumference diametric to said integral connection of both said first tube and said second tube remaining uncovered by said structural material.
 6. The composite panel assembly of claim 5, wherein a first modular building unit is attached to a second modular building unit, said modular building units being disposed parallel, within the same plane, and having an attachment between said uncovered portion of the outer circumference of one of said tubes of said first modular building unit and said uncovered portion of the outer circumference of one of said tubes of said second modular building unit.
 7. The composite panel assembly of claim 6, wherein a filler material is disposed within said tubes.
 8. The composite panel assembly of claim 6, wherein abutting surfaces of said structural material on said first modular building unit and said second modular building unit are bonded together to increase the strength of said attachment between said modular building units.
 9. The composite panel assembly of claim 8, wherein a filler material is disposed within said tubes.
 10. A protective shelter that protects an inner space, comprising: a front wall, said front wall having a door frame assembly therein and a door attached to said door frame assembly; a rear wall; two side walls; and a ceiling panel; wherein said walls and said ceiling panel each comprise a composite panel assembly, said composite panel assembly comprises a plurality of modular building units, each of said modular building units comprises a first tube, a second tube aligned immediately adjacent and parallel to said first tube, and at least one integral connection between the outer circumference of said first tube and the outer circumference of said second tube.
 11. The protective shelter of claim 10, wherein said composite panel assembly comprises a plurality of interconnected modular building units wherein a first modular building unit is attached to a second modular building unit, said modular building units being disposed parallel, within the same plane, and having an attachment between the outer circumference of one of said tubes of said first modular building unit and the outer circumference of one of said tubes of said second modular building unit.
 12. The protective shelter of claim 11, wherein a filler material is disposed within said tubes.
 13. The protective shelter of claim 10, further comprising a structural material disposed about the outer surface of said modular building units.
 14. The protective shelter of claim 13, wherein said structural material is disposed in a manner providing the outer surface of said structural material a rectangular cross section, a portion of said outer circumference diametric to said integral connection of both said first tube and said second tube remaining uncovered by said structural material.
 15. The protective shelter of claim 14, wherein a first modular building unit is attached to a second modular building unit, said modular building units being disposed parallel, within the same plane, and having an attachment between said uncovered outer circumference of one of said tubes of said first modular building unit and said uncovered outer circumference of one of said tubes of said second modular building unit.
 16. The protective shelter of claim 15, wherein a filler material is disposed within said tubes.
 17. The protective shelter of claim 15, wherein abutting surfaces of said structural material on said first modular building unit and said second modular building unit are bonded together to increase the strength of said attachment between said modular building units.
 18. The protective shelter of claim 17, wherein a filler material is disposed within said tubes.
 19. The protective shelter of claim 18, wherein both the inner upper ends and inner lower ends of said tubes each further comprise at least one fastening hole, wherein an upper connecting means comprises an L-bracket disposed along the upper end of each of said walls for fastening said ceiling panel to said walls, wherein wall bolts and ceiling bolts pass through both said L-bracket and said fastening holes into at least one receiving nut disposed within said tubes and aligned with said fastening holes, and further wherein a lower connecting means comprises an L-bracket disposed along the lower end of each of said walls for fastening said walls to a base, wherein said wall bolts pass through both said L-brackets and said fastening holes into said at least one receiving nut disposed within said tubes and aligned with said fastening holes and wherein base bolts pass through said L-bracket and anchor into said base, thereby fixedly anchoring said walls to said base.
 20. A protective shelter that protects an inner space, comprising: a front wall, said front wall having a door frame assembly therein and a door attached to said door frame assembly; a rear wall; two side walls; and a ceiling panel; wherein said walls and said ceiling panel each comprise a composite panel assembly, said composite panel assembly comprises, a plurality of modular building units, each of said modular building units comprises, a first tube; a second tube aligned immediately adjacent and parallel to said first tube; and at least one integral connection between the outer circumference of said first tube and the outer circumference of said second tube, a structural material disposed about the outer surface of said plurality of modular building units, wherein said structural material is disposed in a manner providing the outer surface of said structural material a rectangular cross section with a portion of said outer circumference diametric to said integral connection of both said first tube and said second tube remaining uncovered by said structural material, wherein a first modular building unit is attached to a second modular building unit, said modular building units being disposed parallel, within the same plane, and having an attachment between the outer circumference of one of said tubes of said first modular building unit and the outer circumference of one of said tubes of said second modular building unit, abutting surfaces of said structural material on said first modular building unit and said second modular building unit being bonded together to increase the strength of said attachment between said modular building units, wherein both the inner upper ends and inner lower ends of said tubes each further comprise at least one fastening hole, wherein an upper connecting means comprises an L-bracket disposed along the upper end of each of said walls for fastening said ceiling panel to said walls, wherein wall bolts and ceiling bolts pass through both said L-bracket and said fastening holes into at least one receiving nut disposed within said tubes and aligned with said fastening holes, and a lower connecting means comprises an L-bracket disposed along the lower end of each of said walls for fastening said walls to a base, wherein said wall bolts pass through both said L-brackets and said fastening holes into said at least one receiving nut disposed within said tubes and aligned with said fastening holes and wherein base bolts pass through said L-bracket and anchor into said base, thereby fixedly anchoring said walls to said base. 